It is common for modern electronic circuits to use a switching device such as a power field effect transistor (FET) to control the application of current to an electrical load. The switching device is typically arranged in series between a voltage source and the load so that, when an appropriate voltage is applied to a gate terminal, a source-to-drain conduction path is established through the device which allows current to flow to the load.
It is generally desirable to protect a switching device against overloading in order to prevent damage to the device as a result of excessive heat dissipation and other effects. Particularly, if an electrical short occurs in the load, virtually all of the supply voltage is provided across the switching device at substantially all of the available current that can be supplied by the voltage source.
Accordingly, there is a continued need for improvements in the art to provide current limit protection for switching devices, and it is to such improvements that the present invention is directed.